Dr. Gregory W. Albers' career focus has been patient-oriented research in cerebrovascular disease at Stanford University Medical Center. His research accomplishments include significant contributions to the fields of stroke diagnosis, treatment and prevention. He has also played a major role in developing national clinical practice guidelines for patients with cerebrovascular disease. He has been a successful mentor for multiple young stroke investigators and eight of his mentees currently hold full-time academic appointments at university medical centers. Dr. Albers' current research interest is evaluating the utility of new MRI techniques, particularly diffusion and perfusion MRI, as diagnostic and therapeutic decision making tools for patients with acute stroke. The K24 Award will allow him to focus his efforts on facilitating the career development of several junior clinical investigators. The research proposal consists of three funded NIH R01 grants. The DEFUSE study is an NIH funded pilot clinical trial grant that aims to identify specific patient subgroups, defined by diffusion and perfusion MRI profiles, who are likely to have a favorable response to intravenous thrombolytic therapy when treated between 3 and 6 hours after stroke symptom onset. This pilot trial will provide essential data needed to design a randomized clinical trial to determine whether stroke patients, selected with specific MRI criteria, can benefit from intravenous thrombolytic therapy beyond 3 hours after stroke onset. The DIAGNOSIS trial is a 4-year, single-center NIH funded trial designed to determine the clinical utility of diffusion and perfusion MRI in patients presenting within 72 hours of the onset of symptoms suggestive of brain ischemia. A third NIH funded R01 grant will employ sophisticated MRI techniques to measure cerebral perfusion in acute stroke patients and determine quantitative thresholds for differentiating critical levels of hypoperfusion from benign oligemia. An innovative mentoring program is proposed that will prepare young investigators for careers in clinical research. This K24 research program will expand Dr. Albers' skills as a clinical investigator and allow him to become a more effective mentor. [unreadable] [unreadable]